Answer: 1/5
Step-by-step explanation:
Answer:
Step-by-step explanation:
3y+5y=8y
8y=7(divide 8 in both sides to get y)
y=7/8
x+2y=3...but we already know the value of y, so substitute 7/8 to y
x+2(7/8)=3
x+14/8=3
x=3-14/8
=1.25
-8, -48, -288
or
-8, -4/3, -2/9
Answer:
yes
Step-by-step explanation:
Answer:
The standard deviation of weight for this species of cockroaches is 4.62.
Step-by-step explanation:
Given : A different species of cockroach has weights that are approximately Normally distributed with a mean of 50 grams. After measuring the weights of many of these cockroaches, a lab assistant reports that 14% of the cockroaches weigh more than 55 grams.
To find : What is the approximate standard deviation of weight for this species of cockroaches?
Solution :
We have given,
Mean 
The sample mean x=55
A lab assistant reports that 14% of the cockroaches weigh more than 55 grams.
i.e. P(X>55)=14%=0.14
The total probability needs to sum up to 1,



The z-score value of 0.86 using z-score table is z=1.08.
Applying z-score formula,

Where,
is standard deviation
Substitute the values,





The standard deviation of weight for this species of cockroaches is 4.62.